The present invention is directed to a deck screw intended for use with composite
lumber, although it can be used with other wood products, such as pressure treated
lumber. The deck screw of the present invention may be provided with a head and
a shaft that has two regions of varying diameter. The upper region has threads
that exceed the number of threads of the lower shaft, on a unit length basis. The
threads of the upper shaft may be configured in an inverted buttress design. The
lower region of the shaft terminates at a tapered distal end having a pointed tip
that leads the screw through the wood material. Threads are provided on the lower
region of the shaft. The head of the screw is provided with an upper surface, a
lower surface, and a crown that extends around the perimeter of the head, The crown
extends beyond the lower surface of the head, forming a recessed region between
the lower edge of the crown and the shaft of the screw. The head may also be provided
with an undercut. Further, the head of the screw may be provided with a square
driver opening that permits the persons installing the screw to use a square bit.
For instance the opening may be a #2 square driver opening. It should be understood
that Phillips heads or flat heads in various sizes might also be employed.